Synchronous XMLHttpRequest

to be deleted , not a real error …

This isn’t coming from us. Here’s our only usage of open(): https://github.com/getsentry/raven-js/blob/master/src/raven.js#L1450

With that said, raven-js wraps the entire XHR object so it ultimately looks like it’s coming from us, but it’s not. Something else is the culprit here, we’ve just gotten in the way for debugging purposes so we can capture our information.

Because of exactly as I just said. :slight_smile:

We wrap the XHR object and we’re just passing along arguments, as you can see here from this code. We’re not doing anything other than passing along what the caller did. In your case, something other than is is calling open() with an async=false argument. We don’t go out of our way to change behavior.